Chemical Extraction of Microorganisms From Water-Saturated, Packed Sediment
Author: Fabio Ugolini, Martin H. Schroth, Helmut Burgmann, Frederik Hammes, Josef
Source: Water Environment Research
Publisher: Water Environment Federation
Abstract:Microbial characterization of aquifers should combine collection of suspended and attachedmicroorganisms (biofilms). We investigated chemical extraction of microorganisms fromwater-saturated, packed sediment containing established biofilms by comparing differentdetachment-promoting agent (DPA) solutions with tap water as eluent in columnexperiments. Extraction efficiency was determined from cell concentrations in the columneffluent. Adenosine tri-phosphate concentrations were measured to confirm cell extractionand as an indicator of cell-membrane integrity. Quality of extracted bacterial communitieswas assessed by comparing their terminal-restriction-fragment-length-polymorphism profiles with destructively sampled sediment-community profiles. Extraction efficiency increasedmore than eight-fold when deionized water, D-amino acids or enzymes were used as DPA.Community profiles recovered by individual DPA solutions showed more profounddifferences at the level of rare microbial groups, while abundant groups appeared ubiquitousacross treatments. Our results suggest that comparison of communities extracted by differentDPAs may provide improved information on rare microbial groups in biofilms.
Keywords: detachment, biofilm, sediment, T-RFLP, flow cytometry, ATP
Appeared or available online: January 3, 2013